Thor Mining spiked over 70% today, but the AIM-listed miner involved in gold, tungsten-molybdenum and rare earth elements in Australia, insists it isn't hiding anything."Following the movement in the Thor share price this morning and the increase in market volume the directors are not aware of any information that has not been announced to the market which explains the movement in the recent trading of securities of the company," said the group which hasn't traded this high since 2008."Further the company is not in possession of any information requiring an announcement."A recent increase in the price of gold and tungsten and encouraging exploration activities at the Dundas gold project may have helped, it said.It thinks the shares have been "depressed and below their underlying value", perhaps due to the long delay in restarting mining at the Molyhil molybdenum/tungsten project due to unfavourable commodity pricing. "Recently the Tungsten prices have recovered strongly to historical highs and investors may be aware of this," it said.